G'day Phil,
The 1962-3 Model 502 Envoy looks about the closest match to this one. That model had a Zenith carby, so a pic of the carby is needed to confirm that.
The Envoy just had a '4 Stroke' decal across the front of the tank, but it's quite on the cards that your machine is a 'storebrand' variant.
Cheers,
Gadge
"ODK Mods can explain it to you, but they can't understand it for you..."
"Crazy can be medicated, ignorance can be educated - but there is no cure for stupid..."
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